第76章 对火星轨道变化问题的最后解释(8/10)

haninthepanelsdeotal9.actually，thefluctuationsintheinner4panelsareteextentasaresultoftheorbitalvariationofthemercury.however，weothetributionfromotherterrestrialplas，aswewillseeinsubsequeions.

4.4long-termcouplingofseveralneighbplapair

letusseesomeindividualvariationsofplaaryorbitalenergyandangularmomentumexpressedbythelow-passfiltereddelaunayelements.figs10and11showlong-termevolutionoftheorbitalenergyofeachplaandtheangularmomentuminn 1andn?2iioicethatsomeplasformapparentpairsintermsoforbitalenergyandangularmomentumexge.inparticular，venusahmakeatypicalpair.inthefigures，theyshowivecorrelationsinexgeofenergyandpositivecorrelationsinexgeofangularmomentum.theivecorrelationinexgeoforbitalenergymeansthatthetwoplasformacloseddynamicalsystemintermsoftheorbitalenergy.thepositivecorrelationinexgeofangularmomentummeansthatthetwoplasaresimultaneouslyundercertainlong-termperturbations.didatesforperturbersarejupiterandsaturn.alsoinfig.11，weseethatmarsshows'itivecorrelationintheangularmomentumvariationtothevehsystem.mercuryexhibitscertaiivecorrelationsintheangularmomentumversusthevehsystem，whichseemstobeareacausedbytheservationofangularmomentumierrestrialplaarysubsystem.

itisnotclearatthemomentwhythevehpairexhibitsaivecorrelationinenergyexgeand'itivecorrelationinangularmomentumexge.ossiblyexplainthisthroughthegeneralfactthattherearenoseculartermsinplaarysemimajoraxesuptosed-orderperturbationtheories(cf.brouwerboccalettipucacco1998).thismeansthattheplaaryorbitalenergy(whichisdirectlyrelatedtothesemimajoraxisa)mightbemuchlessaffectedbyperturbingplahanistheangularmomentumexge(whichrelatestoe).heheetricitiesofvenusahbedisturbedeasilybyjupiterandsaturn，whichresultsin'itivecorrelationintheangularmomentumexge.oherhand，thesemimajoraxesofvenusaharelesslikelytobedisturbedbythejovianplahustheenergyexgemaybelimitedonlywithinthevehpair，whichresultsiivecorrelationintheexgeoforbitalenergyinthepair.

asfortheouterjovianplaarysubsystem，jupiter–saturnanduranus–uomakedynamicalpairs.however，thestrenhoftheircouplingisnotasstrongparedwiththatofthevehpair.